Practice Test Geeks(CLS) Certified Lubrication Specialist Practice Test
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Lubricant Selection & Management Flashcards

7 cards from real CLS practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Lubricant Selection & Management flashcards as text

  1. When consolidating lubricants in a plant, what is the primary goal of a lubricant rationalization program?

    Answer: Reduce the number of lubricant products without compromising equipment protection

    Lubricant rationalization aims to minimize the variety of lubricants used by finding compatible equivalents, reducing cross-contamination risk and inventory costs.

  2. A plain journal bearing operates under high load and low speed. Which lubrication regime is most likely present?

    Answer: Boundary lubrication

    High load with low speed reduces the oil film thickness below a critical level, resulting in asperity contact characteristic of boundary lubrication.

  3. Which test method is most commonly used to determine the water content of an in-service lubricant?

    Answer: Karl Fischer titration

    Karl Fischer titration is the standard, precise method for quantifying water content in lubricating oils.

  4. A lubricant supplier provides a product with an ISO 6743-4 classification of HM. This indicates the hydraulic fluid contains:

    Answer: Anti-wear additives

    ISO 6743-4 HM classification designates mineral hydraulic fluids with anti-wear (AW) additives for use in high-pressure hydraulic systems.

  5. Which property of a grease is defined by the ASTM D217 worked penetration test?

    Answer: Consistency (NLGI grade)

    ASTM D217 measures worked penetration (in tenths of a millimeter) which directly determines the NLGI consistency grade of a grease.

  6. A technician is selecting a lubricant for an electric motor bearing that operates at moderate speed and temperature. What is the preferred lubricant type?

    Answer: NLGI 2 lithium complex grease

    NLGI 2 lithium complex grease is the most widely used lubricant for electric motor bearings due to its good temperature range, compatibility, and water resistance.

  7. Which of the following base oil types is completely miscible with water and requires special seal compatibility consideration?

    Answer: Polyalkylene glycol (PAG)

    PAG-based lubricants are water-miscible (hygroscopic), making them incompatible with many standard elastomer seals and petroleum-based lubricants.